Microsoft Word - Environmental benefits of recycling 2010 update.doc

(Jeff_L) #1

Study no 5


This study consists of an LCA of two treatment options for plastics wastes from discarded TV sets. All steps
starting from the extraction of the resources required for the plastics production and up to the incineration or
recycling into new TV sets are included. At the disposal stage, incineration with energy recovery and recycling are
compared for a mix of PE, PS and PVC regarding depletion of natural resources and climate change. Recycling is
found to be preferable to incineration for both indicators.


Study no 6


This study compares recycling, incineration with energy recovery and landfill for HDPE, LDPE and PET regarding
only two indicators: climate change and energy demand. Once again, recycling appears as the best alternative.
Thanks to the energy credit, incineration performs better than landfill in terms of energy demand. However,
landfill is preferred to incineration for climate change since no emissions are accounted for during the 100-year
time period considered.


Study no 7


This study compares recycling and landfill for PET, HDPE and PVC. For climate change and energy demand,
recycling performs better. For water consumption, the picture is less clear since recycling is preferred for PVC but
not for PET and HDPE. It is indeed assumed in the study that no water is consumed in the event the material is
landfilled and that for PET and HDPE recycling water use (due to washing the collected plastics) is higher than
water use in avoided virgin plastic production.


Study no 8


This LCA looks at the complete end-of-life of different types of plastics and bioplastics packaging. For plastics,
three different recycling scenarios are compared to incineration with energy recovery for recycled PS packaging
(made from polystyrene production wastes). Two of the three recycling scenarios correspond to mechanical
recycling scenarios in which the PS is regranulated into similar material. The difference between both scenarios is
that the recycling scenario from case 8[PS2] includes the avoided material production within the system
boundaries while the other one from case 8[PS3] does not. In this latter case, the recycled material is assumed to
be sold on the market with a large range of possible applications that have not been modelled. The remaining
recycling scenario, from case 8[PS1], is a feedstock recycling scenario in which the PS is recovered in blast
furnaces and used as a replacement for coke. Feedstock recycling which, as already mentioned, can be defined
as a change in the chemical structure of the material, where the resulting chemicals are used for another purpose
than producing the original material. The use of PS as a reducing agent in blast furnaces is usually considered to
fall under this definition. It is debatable whether the scenario should be classified as recycling rather than energy
recovery but the choice has been made in this review to refer to it as a recycling scenario as argued above.


Regarding climate change, the three recycling scenarios perform better than incineration with energy recovery.
Concerning the energy demand, the mechanical scenarios are more advantageous than incineration but
incineration is preferable to feedstock recycling.

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